EDS200H5 Chapter Notes - Chapter 4: Nicotine, Muscle Tone, Apgar Score
Document Summary
By the time babies are born, they have approximately 100 billion neurons, or nerve cells, which handled information at the cellular level in the brain. The basic architecture of the brain is assembled during the first two trimesters of the prenatal development. Neural tube forms at about 18 to 24 days after conception. Generation of new neurons is called neurogenesis. Neuronal migration: 6-24 weeks cells moving outward from their point of origin to their appropriate locations and migrated to its target destination. At about the 23rd prenatal week, connections between neurons begin to occur. Teratogen: any agent that cause a birth defect or negatively alters cognitive and behavioural outcomes. The field of study that investigates the causes of birth variations is called teratology. Difficult to determine which one causes which problem. Three things influence both the type and severity of the effect: dose-response relationship.
